This invention relates to a foot activated starting aid specifically for hand held equipment employing a internal combustion with a pull cord starter mechanism.
Small, internal combustion engines have utilized the pull cord starting mechanism as a standard in the industry for a long time. These engines are commonly used in chain saws, string trimmers, leaf blowers. This action is fairly easy for an adult male without any physical handicap. Thus, any person with a physical limitation of upper body strength was precluded from starting their yard equipment or cutting their own wood with a chainsaw.
Other starting devices and aids have been tried and used to ease the abrupt back pulling physical force needed to start a hand held engine powered machine. One is a partial compression release valve that opens during the starting period of time. This method of easing the possible compression ignition kick back is troublesome because of possible compression loss during engine running causing power loss and also poor fuel-air ignition during starting operation on small engines.
Electric starters with self contained rechargeable batteries have been used but this method adds extra weight to the hand held machine and the unreliability of a fully charges battery leaves no other way to start the engine when a low charged battery is in the machine.
In search for other mechanical devices to aid the starting of portable hand held machines that are powered by a internal combustion engine that have an existing pull cord starting device, none was found.
Foot starting aids were researched for push-type and motorized lawnmowers including: U.S. Pat. No. 2,850,003 (1958) to Konle; U.S. Pat. No. 3,040,726 (1962) to Mayer; U.S. Pat. No. 3,174,471 (1965) to Welglage et al.; U.S. Pat. No. 3,381,677 (1968) to Hunter; U.S. Pat. No. 3,885,544 (1975) to Pfeiffer; U.S. Pat. No. 4,109,538 (1978) to Glenday ed al.; U.S. Pat. No. 4,257,367 (1981) to Fujikawa et al.; U.S. Pat. No. 4,397,274 (1983) to Tarnedde; U.S. Pat. No. 5,133,312 (1992) to Schede. They are not applicable to hand held, portable machines.
The main object of the invention is to change the physical effort of using a person""s hand, arm, shoulder and upper back muscles to using the sizable and vital muscles of the leg and foot for the main thrust of a person""s effort on starting a portable hand held combustion engine machine. A person""s activities of daily living such as walking, climbing, going to a flight of stairs is what is needed and used to operate this foot operated starting aid. It should be noted here that these activities are also necessary to use the machines for their said purpose.
Another advantage of the invention is built into the design as the xe2x80x9cmeans of holdingxe2x80x9d the equipment in place while the engine is being started. Due to the small engine""s possible compression-ignition kick-back, it can cause loss of standing posture balance to the person attempting to start the machine with its pull cord starter only. This foot powered starting aid provides a positive controlled fast pull to the existing pull cord starter mechanism of small engines with out the possible physical harm done to an operator.
Also relating another advantage to the xe2x80x9cmeans of holdingxe2x80x9d the independent foot starting aid provides is the ability of the machine operator to use both hands to adjust the choke and carburetor.
Further relating to the advantage the xe2x80x9cmeans of holdingxe2x80x9d the independent foot starting aid provides is the conversion of physical effort that is exerted by the use of pulling the existing starting pull cord by hand, possibly many times.
An object of the invention is to provide a starting aid that can be fabricated from commonly available materials that are low in cost and use existing methods of fabrication.
A further object of the invention is the provision of a piece of equipment that requires no further lubrication or extensive maintenance.
An advantage to the invention with foot power depressing the foot pedal from the upper end of the foot pedal""s arc swing, to the base, causes a multiplied travel of one to two (1:2) of the down travel of the pulley on the foot pedal in relation to the pull travel of the handle on the free end of the engine starter pull cord. For every one inch of down travel of the pulley on the foot pedal there is a 2 inch pull travel transmitted by the cable to the handle on the free end of the engine starter pull cord.
Also inherent to the advantage of using a foot pedal for power gives the action of depressing the pedal with a person""s foot and in turn causes the engine to rotate twice as fast or maybe faster than the backward pull of the starter pull cord with an exerted effort a person""s hand, arm, shoulder and upper back muscles during the starting operation of the engine.
Another advantage of the invention specifically gives 4 advantageous benefits to rotating a two stroke cycle internal combustion engine faster, during the starting phase of starting a internal combustion engine with this invention. They are: A) better carburation, B) higher compression, C) better ignition, D) less chance of xe2x80x9ccompression ignition kickbackxe2x80x9d.